1. Field of the Invention
The present invention relates to a wireless LAN device capable of performing wireless communication using a plurality of channels.
2. Description of the Background Art
Wireless LAN has been widespread in recent years. In a wireless LAN, wireless LAN devices perform communication with each other within the coverage area of the wireless LAN devices. When it is desired to perform communication over a wide area exceeding the coverage area of a wireless LAN device, a plurality of wireless LAN devices are installed to wirelessly relay a packet via these wireless LAN devices, as disclosed in Japanese Laid-Open Patent Publication No. 2004-248289, for example.
In order to realize such wireless relay of a packet among the plurality of wireless LAN devices, a wireless LAN device needs to detect another wireless LAN device. One method to detect another wireless LAN device is as follows. One wireless LAN device acts as a station (non-access point station) that is communicably connectable to another wireless LAN device acting as an access point, and the wireless LAN device transmits a probe request to the other wireless LAN device. The other wireless LAN device (access point) receives the probe request, and transmits a probe response. Then, the wireless LAN device (station) receives the probe response to detect the other wireless LAN device (access point). In this method, however, if these wireless LAN devices are allowed to use a plurality of channels, the wireless LAN device that performs detection does not know which channel the other wireless LAN device currently uses and, therefore, has to frequently change the channel to transmit the probe request. If the wireless LAN device that performs detection acts as an access point and communicates with a station, it is difficult to maintain the communication with the station.